JP3749854B2 - Steel pipe pile coating protection method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for coating corrosion prevention of steel pipe piles exposed to severe corrosive environments such as the ocean and rivers, and in particular, has a long-term durability and is an anticorrosion method that does not require maintenance, and for fixing a coating anticorrosive material. Therefore, the present invention relates to a method for covering and preventing corrosion of steel pipe piles that is aesthetically pleasing. In addition, in this invention, it can apply not only to a steel pipe pile but a steel pipe sheet pile. Hereinafter, a steel pipe pile includes a steel pipe sheet pile depending on the case.
[0002]
[Prior art and problems to be solved by the invention]
Steel pipe piles and steel pipe sheet piles placed on the sea floor in harbors and the like are prone to severe corrosion, particularly in the vicinity of the splash tidal zone. For this reason, it is necessary to provide corrosion protection to such steel pipe piles and steel pipe sheet piles.
[0003]
Conventionally, as a coating anticorrosion method for such steel pipe piles, a petrolatum-based anticorrosive material is used as an anticorrosive material, and a plastic or titanium cover is attached as the protective material (petrolatum lining method) or mortar is made of plastic. It is common to use a mortar lining method (for example, port steel structure anticorrosion / repair manual (revised version), Coastal Development Technology Research Center, etc.).
[0004]
Also, in such a conventional technology, when these protective covers are attached to a material to be protected, they are often fixed with bolts and nuts, and therefore, a fastening structure is a flange-shaped one attached to the protective cover. (For example, Japanese Patent No. 2511296, Japanese Patent Publication No. 2-19253).
[0005]
On the other hand, as a method for attaching a protective cover having no flange shape, a method of attaching a jig such as a stud bolt to a body to be protected by welding or the like and fixing the jig to the jig is employed.
[0006]
Conventionally, this type of coated anticorrosive material has a predetermined thickness and strength by repeatedly laminating glass fiber reinforced plastic (FRP) manually by using corresponding molds in order to correspond to various steel pipe pile diameters. A common method is to create a protective cover.
[0007]
These methods can produce protective covers tailored to the pile diameter, but each must have a corresponding mold, and manual lamination requires a lot of labor and time until the resin hardens. Can not be removed from the mold, so continuous work is not possible. Further, since a large force is applied to the fastening flange portion by tightening the bolt, it is necessary to make the fastening flange portion thicker than the other portions of the protective cover.
[0008]
On the other hand, as a method of using a mechanical molding material, a method of creating a coated anticorrosive material by dividing into an angle-shaped flange portion serving as a fastening portion of a protective material and a plate material serving as an anticorrosion portion, and combining them is generally used. As a bonding method thereof, a method in which a heating wire is provided between the two made of a thermoplastic resin and heat-sealed (Japanese Examined Patent Publication No. 61-32468), and a method in which both are bonded with an adhesive (Actual 3-22273). No. Gazette). In some cases, the coated anticorrosive material is continuously machine-molded with a polyolefin resin (Japanese Patent Laid-Open No. 59-62110).
[0009]
However, according to the method described in Japanese Patent Publication No. 61-32468, it is possible to produce a coated anticorrosive material with less production effort and a constant finish, but the bonded end portion of the fused angle material and plate material is When tightening and fixing with bolts, it spreads due to the reaction of the tightening force, and over time, a force that peels like a wedge acts, which may cause damage in a marine environment with a lot of waves.
[0010]
In addition, as in the method described in Japanese Utility Model Publication No. 3-22273, there is a method in which an angle material and a plate material are bonded with an adhesive, and a plate made of the same material as the plate material is also attached to the upper side of the angle material. However, the method according to No. 1 is inferior in long-term durability since the adhesive force decreases with time. Particularly in the marine environment, repeated stress angle portions are easily received due to waves, tidal currents, and the like, and this often causes problems of peeling and dropping.
[0011]
Further, when the entire coated anticorrosive material is machine-formed at once, if the coated anticorrosive material is fixed in a flange form, the thickness is insufficient, so that the bolt cannot be sufficiently fixed by tightening. On the other hand, if the plate thickness is increased due to the flange, the entire coated anticorrosive material becomes heavy, so that the workability of the mounting operation is remarkably lowered and the cost is increased.
[0012]
These coated anticorrosive materials are made of plastic materials, but coated anticorrosive materials for machine-formed products made of titanium are also used (Japanese Patent Publication No. 2-19253). According to this method, since titanium having excellent corrosion resistance in the marine environment is used, it becomes a coated anticorrosive material having higher strength and durability than a plastic material. Since the plate thickness is thin, it will bend by bolting. Therefore, in order to maintain the flange structure, it is necessary to attach the molded angle material as a protective material.
[0013]
Further, a coated anticorrosive material may be prepared using an ultraviolet curable FRP tape. This makes it possible to produce a coated anticorrosive material that does not require a flange, but because it is UV-cured, it is difficult to cure in water, and a dedicated UV-irradiation device is required in places where UV radiation is insufficient in the atmosphere. It becomes.
[0014]
In addition, there are those in which the shape of the flange and the material of the protective material are changed, but the problems described above are included. Furthermore, as a lining method in water, there is a method in which a low-viscosity and high-viscosity resin is coated and impregnated into a nonwoven fabric and integrated with a rubber sheet or the like to spread and prevent corrosion between steel materials (Japanese Patent Publication No. 3-36909), This method is impregnated with two kinds of resins, and does not mention a practical and specific method for fixing the anticorrosion layer at the joint portion of the coating layer to the steel pipe pile.
[0015]
In addition, for steel pipe sheet piles, a bolt for attaching a protective cover is attached to the section between the steel pipes, but since the section interval is not constant, a flange is provided in the steel pipe part to attach a protective cover formed to a certain size, It needs to be adjusted. However, a continuous wall body such as a steel pipe sheet pile is more susceptible to waves and tidal currents than a steel pipe pile, and the protruding flange is easily damaged.
[0016]
Accordingly, an object of the present invention is to provide a method for covering and preventing steel pipe piles that has long-term durability and does not require maintenance without using a fastening flange or bolts and nuts.
[0017]
[Means for Solving the Problems]
As a result of the study, the present inventors have found that the steel pipe pile coating anticorrosion method described below achieves the above object, and have reached the present invention.
[0018]
The present invention has been made on the basis of the above knowledge, and applied or pasted with an anticorrosive material on a steel pipe pile, and the anticorrosive material is wrapped with a plastic or metal protective cover so that the end of the protective cover is wrapped. Form and wrap, press the protective cover with a fastener, and temporarily fix the wrap part with a fixing tool, and then seal the wrap part on the inside of a curved plate-like or channel-like long protective cover An object of the present invention is to provide a method for coating corrosion prevention of a steel pipe pile, characterized in that a material previously coated or impregnated with a material is pressure-fixed and the sealing material is cured.
[0019]
The present invention also applies or impregnates an anticorrosive material to the inner surface of a plastic or metal protective cover, wraps the protective cover around a steel pipe pile so that the end of the protective cover wraps, forms a wrap portion, and tightens Temporarily fix the wrap part with a fixing tool while spreading the protective cover with a tool, and then apply or impregnate a sealing material in advance to the inner side of the curved plate-like or channel-like long protective cover. An object of the present invention is to provide a method for coating corrosion prevention of steel pipe piles, which comprises fixing the above-mentioned material by spreading pressure and curing the sealing material.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a steel pipe pile covering anticorrosion method of the present invention will be described in detail based on the drawings.
[0021]
FIG. 1: is a side view which shows 1st Embodiment of the coating corrosion prevention method of the steel pipe pile of this invention, and shows the state which wound the petrolatum type | system | group anticorrosive material around the steel pipe pile. FIG. 2 is a side view showing a state in which the wrap portion of the protective cover is temporarily fixed with a fixture. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is an enlarged view of a wrap portion of the protective cover of FIG. FIG. 5 is a cross-sectional view showing a state in which a plate-like or channel-like long protective cover is attached to the wrap portion of the protective cover, and a resin that hardens even in water inside is cured. 6 is a cross-sectional view taken along line AA in FIG.
[0022]
In the present invention, the anticorrosive material 2 is applied or pasted to the steel pipe pile 1 and the anticorrosive material is wrapped with a plastic or metal protective cover 3 so that the end of the protective cover is wrapped ( 1-3), or the anticorrosion material 2 is applied or impregnated on the inner surface of the protective cover 3, and the protective cover 3 is wrapped around the steel pipe pile 1 so that the end of the protective cover wraps (not shown). )
[0023]
When the anticorrosive material 2 is applied or pasted to the steel pipe pile 1, a petrolatum-based anticorrosive material is preferably used as the anticorrosive material 2, and the petrolatum-based anticorrosive material is applied or pasted to the steel pipe pile 1 subjected to the ground treatment.
[0024]
Further, when the anticorrosive material 2 is applied or impregnated on the inner surface of the protective cover 3, a resin that cures in water is preferable as the anticorrosive material 2. Resins that can be cured in water (curable resins) are preferably exemplified, and specific examples include epoxy resins, urethane resins, silicone resins, polysulfide resins, and polyester resins.
[0025]
This curable resin desirably contains a water-absorbing polymer. By using the water-absorbing polymer in this way, the moisture on the surface of the steel pipe pile is immediately absorbed by the water-absorbing polymer, and the surface of the steel pipe pile is free of moisture that hinders resin adhesion. Bonding to the pile is easy. Such water-absorbing polymers include polyacrylates, saponified vinyl acetate / acrylate copolymers, polyvinyl acetate / maleic anhydride reactants, cross-linked isobutylene / maleic acid copolymers, polyethylene oxide System, starch / acrylic acid graft copolymer, polyvinyl alcohol system, polyvinyl N-vinylacetamide system, etc., and 1 to 200 parts by weight are added to 100 parts by weight of the curable resin.
The curable resin is preferably added with a water-soluble corrosion inhibitor or oxygen scavenger. Examples of such water-soluble corrosion inhibitors include normal phosphates, polyphosphates, nitrites, and benzoic acid. Salts, silicates and the like are used, and sodium nitrite, hydrazine and the like are used as the oxygen scavenger.
[0027]
It is desirable that a holding layer (not shown) is provided on the outer periphery of the anticorrosion material 2, and the anticorrosion material is protected even when the protective cover 3 is spread by the holding layer, and the gap on the surface of the steel pipe pile 1 is very small. Even a rough surface can be covered without generating a gap. Such a holding layer is composed of a nonwoven fabric, glass fiber, or a raised cloth. This holding layer is affixed to the protective cover 3 with an adhesive.
[0028]
The protective cover 3 is preferably one that is manufactured continuously in a factory, has a softness enough to be wound around the steel pipe pile 1, and has corrosion resistance. As the material of the protective cover 3, glass fiber reinforced plastic using polyester resin, epoxy resin, polypropylene resin, vinyl chloride resin or the like is preferably used as the plastic, and high strength polyethylene can also be used. As the metal, seawater-resistant stainless steel or titanium can be used.
[0029]
Further, a sheet-like foam material such as foamed polyethylene or foamed polyurethane is preferably attached to the inner periphery of the protective cover 3 so as to provide a buffering action, and the thickness is preferably between 5 and 20 mm.
[0030]
Therefore, the coated anticorrosion of the present invention is applied with a sheet-like foam material on the inner periphery of the protective cover 3 as necessary, and further, a holding layer made of a nonwoven fabric or the like is adhered with an adhesive, and the anticorrosive material 2 provided on the inner side thereof. Is a preferred embodiment. Moreover, the protective cover 3 is wound around a steel pipe pile using one sheet or a plurality of sheets according to the diameter of the steel pipe pile 1.
[0031]
A fastening tool 4 such as a belt or a rubber band is provided on the protective cover 3 at an appropriate interval, and the anticorrosive material 2 is spread and fixed. Further, the lap portion is temporarily fixed by a fixing tool 5 such as a rivet.
[0032]
As shown in FIG. 4, holes are drilled at appropriate intervals in the lap portion and a fixing tool 5 such as a rivet is driven and fixed. At this time, the wrap width is desirably 50 mm or more, and the fixtures 5 are desirably arranged in two rows.
[0033]
As shown in FIGS. 5 and 6, the lap portion fixed by a fixing tool 5 such as a rivet is obtained by applying or impregnating a sealing material 7 to a curved plate-like or channel-like long protective cover 6 in advance. Attach what was there. At this time, it is desirable to apply a dedicated primer for adhesion to the surface of the protective cover 3 to which the sealing material 7 is adhered.
[0034]
As the sealing material 7 used here, a resin (curable resin) that can be cured in water similar to that used for the anticorrosion material 2 is preferably exemplified. It is preferable that a water-absorbing polymer, a water-soluble corrosion inhibitor, and an oxygen scavenger are added to the curable resin, similarly to the curable resin used as the anticorrosive material 2.
[0035]
A sufficient amount of the curable resin to be applied or impregnated is set, and the long protective cover 6 is expanded and fixed again by the fastening tool 4 such as a belt or a band, and held until the curable resin is cured. Since the overflow from the long protective cover 6 is not preferable in terms of the finished aesthetics, it is desirable to remove it with a waste or the like before the curable resin is cured.
[0036]
FIG. 7: is a perspective view of the example applied to the steel pipe sheet pile 8 which shows 2nd Embodiment of the coating | coated anticorrosion method of the steel pipe pile of this invention, and it applies to the steel pipe sheet pile 8 instead of the steel pipe pile 1 of FIGS. Except for the above, it is the same as FIGS. Further, the anticorrosion covers of the steel pipe sheet piles 8 are connected and fixed by stud bolts 9.
[0037]
In the present invention, as the protective cover, a cover that can be continuously produced by a machine is used without using a layered cover with a mold matched to the pile diameter. For this reason, a significant cost reduction can be achieved. Furthermore, since the material with a pattern is also included in the choice of a protective cover by continuous production by a machine, when such a protective cover is used, anticorrosion considering the landscape becomes possible.
[0038]
Conventionally, when a machine-formed protective cover is used, a separately processed flange is attached by rivets or welding, and then fastened with bolts and nuts, but in this case, the above-mentioned problems occur. Arise. When using a machine-formed cover without using a flange, a method of welding a stat bolt to a steel pipe and fixing it, or a method of fixing an overlapping portion of the cover with a rivet or a bolt and nut (Japanese Patent Laid-Open No. 2-161020) ) Is performed.
[0039]
However, in this method, sufficient tightening in the circumferential direction cannot be obtained, so that a gap is likely to remain in the cover, and it is difficult to achieve satisfactory coating corrosion protection. In the coating anticorrosion method of the present invention, a protective cover is attached in order to solve these problems, and is then temporarily tightened strongly with a belt or a band, and the lap portion of the protective cover is fixed with a fixing tool such as a rivet. In addition, a plate-like or channel-like cover using a curable resin is attached to prevent the wave force or tidal current from acting like a wedge in the gap between the laps and to prevent corrosion of fixtures such as rivets. . Thereby, the anticorrosion excellent also in aesthetics without a flange becomes possible for a long time.
[0040]
In addition, bolts and nuts used for fixing flanges in the past are made of SUS metal. However, depending on the environment, corrosion problems may occur and bolts and nuts must be replaced for long-term use. Since the flange is not used in the coated anticorrosion method of the invention, this is not the case, and the influence of waves and water flow is reduced, so that the life of the coated anticorrosion can be extended.
[0041]
【The invention's effect】
The coating anticorrosion method of the present invention has long-term durability and does not require maintenance without using a fastening flange or bolts and nuts. Therefore, the coating anticorrosion method of the present invention can be applied to various steel pipe piles and steel pipe sheet piles placed on the seabed in harbors and the like.
[Brief description of the drawings]
FIG. 1 is a side view showing a first embodiment of a steel pipe pile covering anticorrosion method of the present invention and showing a state in which a petrolatum-based anticorrosive material is wound around a steel pipe pile.
FIG. 2 is a side view showing a state in which a wrap portion of a protective cover is temporarily fixed with a fixing tool.
FIG. 3 is a cross-sectional view taken along a line AA in FIG.
FIG. 4 is an enlarged view of a wrap portion of the protective cover of FIG.
FIG. 5 is a cross-sectional view showing a state in which a plate-like or channel-like long protective cover is attached to a wrap portion of the protective cover and a resin that is hardened in water inside is cured.
FIG. 6 is a cross-sectional view taken along the line AA in FIG.
FIG. 7 is a perspective view of an example applied to a steel pipe sheet pile, showing a second embodiment of the steel pipe pile covering anticorrosion method of the present invention.
[Explanation of symbols]
1: Steel pipe pile 2: Anticorrosive material (Petrolatum anticorrosive material or curable resin)
3: Protective cover 4: Fastening tool 5: Fixing tool 6: Plate-like or channel-like long protective cover 7: Sealing material (curable resin)
8: Steel pipe sheet pile 9: Stud bolt

Claims (10)

An anticorrosive material is applied or pasted on the steel pipe pile, and the anticorrosive material is wrapped with a plastic or metal protective cover so that the end of the protective cover is wrapped, and the protective cover is spread with a fastener. While pressing, the wrap part is temporarily fixed with a fixing tool, and then the wrap part is preliminarily coated or impregnated with a sealing material inside a curved plate-like or channel-like long protective cover. A method of covering corrosion prevention of a steel pipe pile, characterized by pressing and fixing the sealing material. Apply or impregnate an anticorrosive material on the inner surface of a plastic or metal protective cover, wrap the protective cover around a steel pipe pile so that the end of the protective cover wraps, and form the wrap part with a fastener. After the wrap portion is temporarily fixed with a fixture while spreading, the wrap portion is preliminarily coated or impregnated with a sealing material inside a curved plate-like or channel-like long protective cover A coating anticorrosion method for steel pipe piles, characterized in that the sealing material is cured by fixing pressure. The method of covering corrosion protection of steel pipe piles according to claim 1, wherein the corrosion protection material is a petrolatum-based corrosion protection material. The method of covering corrosion prevention of steel pipe piles according to claim 2, wherein the anticorrosive material is a resin that is cured in water. The method for covering corrosion prevention of a steel pipe pile according to any one of claims 1 to 4, wherein the sealing material is a resin that is cured in water. The method for coating corrosion prevention of steel pipe piles according to claim 4 or 5, wherein the resin that cures in water contains a water-absorbing polymer, and the content thereof is 1 to 200 parts by weight with respect to 100 parts by weight of the resin. . The method according to any one of claims 4 to 6, wherein a water-soluble corrosion inhibitor is added to the resin that is cured in water. The method of covering corrosion prevention of steel pipe piles according to any one of claims 4 to 7, wherein an oxygen scavenger is added to the resin that is cured in water. The method of covering corrosion prevention of steel pipe piles according to any one of claims 1 to 8, wherein a sheet-like foam material is attached between the protective cover and the corrosion protection material. The steel pipe pile covering anticorrosion method according to any one of claims 1 to 9, wherein the anticorrosive holding layer is provided on the inner surface of the protective cover.

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